A Korean treatment for the vaginal area is said to aid health and fertility. What's missing is evidence.

Pungent steam rises from a boiling pot of a mugwort tea blended with wormwood and a variety of other herbs. Above it sits a nude woman on an open-seated stool, partaking in a centuries-old Korean remedy that is gaining a toehold in the West.

Vaginal steam baths, called chai-yok, are said to reduce stress, fight infections, clear hemorrhoids, regulate menstrual cycles and aid infertility, among many other health benefits. In Korea, many women steam regularly after their monthly periods.

There is folk wisdom — and even some logic — to support the idea that the carefully targeted steam may provide some physiological benefits for women. But there are no studies to document its effectiveness, and few American doctors have even heard of it.

Niki Han Schwarz believes it worked for her. After five steams, she found she had fewer body aches and more energy. She also became pregnant eight months ago at the age of 45 after attempting to conceive for three years.

Han Schwarz and her husband, orthopedic surgeon Charles Schwarz, are determined to introduce vaginal steam baths to Southern California women. Their Santa Monica spa, Tikkun Holistic Spa, offers a 30-minute V-Steam treatment for $50. (The identical treatment is available for men, to steam the perineal area.)

At Daengki Spa in Koreatown, a 45-minute V-Herbal Therapy treatment can be had for $20 a squat. The steam includes a mixture of 14 herbs imported from Korea by spa manager Jin Young. The spa's website claims the treatment will "rid the body of toxins" and help women with menstrual cramps, bladder infections, kidney problems and fertility issues. "It is a traditional Korean health remedy," according to the website.

Across the country, chai-yok treatments are not easy to find. They are available in a scattering of alternative holistic health centers. The flashy Juvenex Spa in Manhattan offers its 30-minute Gyno Spa Cure for $75. A complete setup for a do-it-yourself steam — open-seated stool, boiler and herbs — can be purchased online at http://www.rakuten.com for $330.

The two predominant herbs in the steam bath mixture are mugwort and wormwood. Mugwort (Artemisia vulgaris) has been used in Eastern medicine for hundreds of years to balance female hormones. It contains natural antibiotics and antifungal agents, according to herbalists and alternative medicine journals. It is also said to stimulate the production of hormones to maintain uterine health, protect the uterus from ulcers and tumors, stimulate menstrual discharge and ease fatigue, headaches, abdominal discomfort and nausea, among other claims.

Wormwood (Artemisia herba), an antimicrobial "cooling herb," is also popular in Eastern medicine. It has been used historically to induce uterine contractions and treat bladder infections, fevers, open sores, constipation, diarrhea, hepatitis, jaundice, eczema and parasitic infections. The leaves and young shoots are antibacterial and antiviral, and they also relax the blood vessels and promote the discharge of bile, according to historical tradition.

Neither herb has been subjected to the rigorous analysis used to vet Western medicines. But Han Schwarz says she and her husband became persuaded by the herbs' healing abilities after conducting a fact-finding mission in South Korea. They discovered that people there used the herbs to aid digestive disorders and immune system strength, for reduction of headaches and pain from inflammatory conditions, to improve energy, to regulate the menstrual cycle and hormones, and to detoxify the uterus.

One of their clients, Sherman Oaks-based writer Lanee Neil, said she prefers the V-Steam to the harshness of a douche and thinks of it as a "facial" for her private area.

"It's a simple, relaxing treatment," says Neil, who hopes it will help her become pregnant. "You can imagine people doing this in the forest somewhere."

Tae-Cheong Choo, who teaches at Samra University of Oriental Medicine in Los Angeles, strongly endorses chai-yok treatment, especially for gynecological problems and infertility. He says he used to administer it to his patients in Korea, but he doesn't have the time to prepare the formula here.

"Many infertility problems are related to coldness and stagnation," Choo says. "The chai-yok treatment is effective for coldness or poor circulation in the lower part of the body because it increases the blood circulation, and blood supplies nutrition, so the more blood supply, the faster the healing process."

Dr. Suzanne Gilberg-Lenz, an obstetrician and gynecologist at Women's Care of Beverly Hills Medical Group, says the idea of steaming the pelvic area is "not insane." The heat boosts circulation, and the increased blood flow brings more oxygen and "immune factors" to the region, she says.

However, she notes, it's impossible to say whether the herbal steam does any good.

"Most of these kinds of treatments are not put through intensive clinical trials, so it becomes challenging to evaluate the actual impact they have," she says. In addition, traditional practices like chai-yok "have been cut off from the larger system they grew out of, including factors of cultural and family life, diet, environment, etc. There's a bigger picture that we're really missing."